The invention relates to an automated shift transmission for a commercial motor vehicle.
From the DE 42 26 576 C2 a car transmission is well-known, which is implemented as a split path transmission and features transmission steps between two adjacent speeds that are unequal in size.
From EP 0 557 707 B1 a method of shifting a gear-shift transmission is known. This gear-shift transmission is used in a motor vehicle and has two pairs of constant gears and a main, that is, direct transmission path. The transmission is equipped with a plurality of pairs of gearwheels, with a plurality of forward gears shiftable by synchronizer clutches or couplings and comprising gear transmission steps. The transmission also includes a reverse gear. All the gears are shifted only by simultaneous engagement of two clutches associated therewith. Two respective pairs of gearwheels are used for shifting from the first gear to the fifth gear. Pairs of gearwheels of the main transmission are used doubled for shifting two gears in one respective range-change gear shifting. A first pair of gearwheels of the main transmission is connected to a respective further pair of gearwheels in a first range-change gear shift structure for shifting two adjacent gears. A second pair of gearwheels of the main transmission is connected to a respective further pair of gearwheels in a second range-change gear shift structure for shifting two non-adjacent gears. This results in progressive transmission steps.
It is the object of the present invention to create an axially short transmission for commercial vehicles, which nevertheless has a relatively high number of speeds and a large transmission ratio spread.